This invention relates to a helical scanning type video tape recorder (hereinafter abbreviated as a "VTR") for recording, e.g., a video signal on a magnetic tape provided with a perpendicular or vertical magnetization layer, and for reproducing a video signal from the magnetic tape; and, more particularly, relates to a configuration of a rotary head mechanism for use in recording a video signal on the perpendicular magnetization layer and reproducing a video signal from the perpendicular magnetization layer.
Recent improvements in magnetic tapes (video tapes) and magnetic heads have assured high density recording. Therefore, it has been made possible to record data continuously for six to eight hours, via the present VTR system, which is represented by the VHS format or .beta. format. Further, for higher density recording, the so-called vertical (or perpendicular) magnetization recording system has been proposed, in which a magnetic tape provided with a perpendicular magnetization layer is used as a recording medium, in place of the conventional VTR using a magnetic tape provided with a planar magnetization layer. However, difficulties have been encountered in applying said so-called vertical magnetization recording system to a rotary head type VTR based on, e.g., the helical scanning process. With the perpendicular magnetization recording, it is generally necessary to set a video tape between a main magnetic pole and an auxiliary magnetic pole. Particularly with the helical scanning type VTR, it is considered necessary to rotate both the main and auxiliary magnetic poles. However, difficulties have been experienced in devising a mechanism adapted to rotate the main and auxiliary magnetic poles under a condition wherein a magnetic tape helically wound on a cylinder is interposed between both magnetic poles.